Molecular indices, phytoplankton community composition and associated environmental parameters along the West Antarctic Peninsula in summer 2023

As part of the Palmer LTER research program during a 24 day period across January 2023, we conducted oceanographic CTD sampling at 10 sites across the West Antarctic Peninsula (4 on the shelf, 6 on the coast), with a view to link different marine phytoplankton communities to distinct molecular signatures of solid phase extracted (SPE) dissolved organic matter. We include ultrahigh resolution mass spectrometry (Fourier-transform ion cyclotron resonance mass spectrometer, FT-ICR-MS) data, molecular indicies calculated from these data (IPhoto, IDeg, IBio), isotopic (SPE-DOM-d13c) and stoichiometric (SPE-DOC,SPE-DON,SPE-DOS,SPE-DOP) values. These parameters were then compared against the biovolume abundance of different phytoplankton groups, determined through Imaging Flow Cytobot (IFCB) analysis. Additionally, we include basic environmental data (DOC, TDN, Fluorescence, Temperature, Salinity).